Introduction To The Scpi Language - Agilent Technologies N8900 series Operating Manual

Introduction to the SCPI Language

Introduction to the SCPI Language
Keywords
Queries
Command Separators and Terminators
Syntax Conventions
Parameter Types
Device Clear
Introduction
This instrument complies with the rules and conventions of the present SCPI version (see SYSTem:VERSion?).
SCPI (Standard Commands for Programmable Instruments) is an ASCII-based instrument command language
designed for test and measurement instruments. SCPI has two types of commands, common and subsystem.
IEEE-488.2 Common Commands
The IEEE-488.2 standard defines a set of common commands that perform functions such as reset, self-test, and
status operations. Common commands always begin with an asterisk ( * ), are three characters in length, and may
include one or more parameters. The command keyword is separated from the first parameter by a blank space. Use a
semicolon ( ; ) to separate multiple commands as shown below:
Subsystem Commands
Subsystem commands perform specific instrument functions. They are comprised of alphabetically arranged com-
mands that extend one or more levels below the root in a hierarchical structure, also known as a tree system. In this
structure, associated commands are grouped together under a common node or root, thus forming subsystems. A por-
tion of the OUTPut subsystem is shown below to illustrate the tree system. Note that some [optional] commands have
been included for clarity.
OUTPut
[:STATe] OFF|0|ON|1
:PON
:STATe RST|RCL0
:PROTection
:CLEar
Keywords
Keywords, also referred to as headers, are instructions recognized by the instrument. Common commands are also
keywords.
OUTPut is the root keyword, PROTection is a second-level keyword, CLEar is a third-level keyword. Colons ( : ) separate
the keyword levels.
72 Agilent N8900 Series Operating and Service Guide